Crystallization of Fe83B17 amorphous alloy by electric pulses produced by a capacitor discharge

Abstract

International audienceHeating of conductive materials by electric current is used in many technological processes. Application of electric pulses to metallic glasses induces their fast crystallization, which is an interesting and complex phenomenon. In this work, crystallization of the Fe83B17 amorphous alloy induced by pulses of electric current produced has been studied using X-ray diffraction and transmission electron microscopy. Ribbons of the alloy were directly subjected to single pulses of electric current 250 mu s long formed by a capacitor discharge. As the value of integral I(2)dt was increased from 0.33 to 2.00 A(2) s, different crystallization stages could be observed. The crystallization began through the formation of the nuclei of alpha-Fe. At high values of integral I(2)dt, alpha-Fe and tetragonal and orthorhombic Fe3B and Fe23B6 were detected in the crystallized ribbons with crystallites of about 50 nm. Thermal annealing of the ribbons at 600 degrees C for 2 min resulted in the formation of alpha-Fe and tetragonal Fe3B. It was concluded that pulses of electric current produced by a capacitor discharge induced transformation of the Fe83B17 amorphous phase into metastable crystalline products

Novel micro-flat springs using the superior elastic properties of metallic glass foils

“…Alternatively, the glassy foil could be shaped to take a desirable waveform using stressannealing without thermal embrittlement as described by Aljerf [8] or using electric current [10] as long as crystallization is avoided [11].…”